1. Field of the Invention
The present invention related to a wideband low-noise amplifier, and more particularly, to a wideband low-noise amplifier that can provide stable wideband matching characteristics, high power gain characteristics, and low noise figure characteristics simultaneously.
2. Description of the Related Art
Wideband amplifiers capable of low-noise amplifying wideband signals have become necessary due to an increase in the wireless communication data rate.
Such a wideband amplifier has a wider signal band than a conventional narrowband amplifier. Thus, the wideband amplifier has a lower power gain and a higher noise figure than the conventional narrowband amplifier. Therefore, the wideband amplifier requires a trade-off between a wideband matching property, a power gain and a noise figure in the circuit design process.
However, a conventional wideband amplifier provides just a slight improvement in performance, failing to provide a considerable improvement in performance.
In the case of integrated circuits for processing Radio Frequency (RF) signals, selection of a differential structure is advantageous in terms of reducing a noise influence. Also, in the case of a direct-conversion transmitter, selection of a differential structure is advantageous in consideration of the performance degradation due to a Local Oscillation (LO) leakage.
A balun for Single-ended To Differential must be additionally provided to design a differential structure. In such a case, additional power consumption occurs due to the balun. Also, if the frequency is high, good single-ended to differential characteristics are difficult to obtain and the design is complicated.